Pass Aleph 3 clone Class A amp experience

[ppataki]

I have ordered a pair of mono balanced Pass Aleph 3 clone amps from here
I know a took a big risk by doing so but since that is the only way to experience them I thought I would give it a try nevertheless
They shall arrive in about 4 weeks - I will post pictures, subjective experience and measurements also at the listening position (using UMIK-1 as always) compared with my current Hypex NC250MPs (unfortunately I have no other means to measure it but it will suffice for the purpose I guess)

Will be interesting to see if/how they will be able to drive my MCLA system...

Stay tuned!

 

[Blumlein 88]

Pass Labs Aleph 3 power amplifier Measurements

Sidebar 5: Measurements Following its 1/3-power, one-hour preconditioning test the Aleph 3's heatsinks were hot, though not unexpectedly so for a class-A design. The input impedance of the Aleph 3 measured 22.3k ohms. The output impedance was at or under 0.1 ohms up to 1kHz, and just slightly...

www.stereophile.com

I owned the real deal back when. Used it with Quad ESL-63s and a few other speakers.

The price for the clone is awfully cheap.

It could sound strained with some speakers that presented a low impedance with a large phase angle. Anything requiring lots of current. I don't think I found a single ported speaker it would handle including some little Radio Shack Lineaums. Quads with the high impedance at low frequencies it was fine. Maggies with a purely resistive load fine. Sealed box speakers generally okay (like LS3/5a). Klipsch K-horns and LaScala's very good match. It had a hard limit of 8 amps of current, and no more. With your sealed box speaker it should be alright. Headphones, oh yeah. Yes I padded them down and used them with headphones. Also used them with Stax headphones.

 

[ppataki]

Pass Labs Aleph 3 power amplifier Measurements

Sidebar 5: Measurements Following its 1/3-power, one-hour preconditioning test the Aleph 3's heatsinks were hot, though not unexpectedly so for a class-A design. The input impedance of the Aleph 3 measured 22.3k ohms. The output impedance was at or under 0.1 ohms up to 1kHz, and just slightly...

www.stereophile.com

I owned the real deal back when. Used it with Quad ESL-63s and a few other speakers.

The price for the clone is awfully cheap.

It could sound strained with some speakers that presented a low impedance with a large phase angle. Anything requiring lots of current. I don't think I found a single ported speaker it would handle including some little Radio Shack Lineaums. Quads with the high impedance at low frequencies it was fine. Maggies with a purely resistive load fine. Sealed box speakers generally okay (like LS3/5a). Klipsch K-horns and LaScala's very good match. It had a hard limit of 8 amps of current, and no more. With your sealed box speaker it should be alright. Headphones, oh yeah. Yes I padded them down and used them with headphones. Also used them with Stax headphones.

Thanks @Blumlein 88 for sharing your experience!

Actually my next DIY speaker project will be based on a pair of 15" Fane full-range speakers with a sensitivity of 98dB and I guess these amps will be a really good match for those
So even in case they should fail with my MCLAs I might keep them for the next project
(my MCLA has a sensitivity of 96dB so the Pass amps *should* be OK but I am extremely curious to compare them with my current Hypex amps - that is the goal of this whole endeavor actually)

 

[audiophile.1963]

Pass Labs Aleph 3 power amplifier Measurements

Sidebar 5: Measurements Following its 1/3-power, one-hour preconditioning test the Aleph 3's heatsinks were hot, though not unexpectedly so for a class-A design. The input impedance of the Aleph 3 measured 22.3k ohms. The output impedance was at or under 0.1 ohms up to 1kHz, and just slightly...

www.stereophile.com

I owned the real deal back when. Used it with Quad ESL-63s and a few other speakers.

The price for the clone is awfully cheap.

It could sound strained with some speakers that presented a low impedance with a large phase angle. Anything requiring lots of current. I don't think I found a single ported speaker it would handle including some little Radio Shack Lineaums. Quads with the high impedance at low frequencies it was fine. Maggies with a purely resistive load fine. Sealed box speakers generally okay (like LS3/5a). Klipsch K-horns and LaScala's very good match. It had a hard limit of 8 amps of current, and no more. With your sealed box speaker it should be alright. Headphones, oh yeah. Yes I padded them down and used them with headphones. Also used them with Stax headphones.

Hello, I too have seen this clone and I would be tempted to buy it to match it with a pair of Klipsch La Scala that I currently keep disconnected. Do you seriously think it's a good choice? A couple sent to Italy would cost me 516 euros, but my doubt is about assistance if it should have problems or it breaks down where I go? It would be interesting, in addition to knowing how it sounds, to have the schemathics. Let me know
Giuseppe

 

[ppataki]

Hello, I too have seen this clone and I would be tempted to buy it to match it with a pair of Klipsch La Scala that I currently keep disconnected. Do you seriously think it's a good choice? A couple sent to Italy would cost me 516 euros, but my doubt is about assistance if it should have problems or it breaks down where I go? It would be interesting, in addition to knowing how it sounds, to have the schemathics. Let me know
Giuseppe

Mines will arrive today
Won't have much time during the weekend but will post pictures today and then next week I will post my subjective experience and MLP measurements vs. my current NC250MPs

 

[audiophile.1963]

Perfect! Thank you I'll wait for news.
Giuseppe

 

[ppataki]

So here are the pictures

Some initial thoughts:
- shipment was super-fast (7 days from China to Hungary using Fedex)
- cannot complain about the packaging, really well done
- amp looks exactly as on Ebay
- hooked them up using the XLR connectors with my Topping DM7 DAC - zero hiss or noise from the speakers! - that's great; to be honest I was not expecting that
- very faint power buzz from the toroidal transformers but I would say that it is normal (my 1500VA toroidal isolation transformer does the same)
- it runs hot (no surprise for a class A amp) - but not superhot

Later on I will share some MLP measurements and subjective listening experience

 

[Blumlein 88]

Hello, I too have seen this clone and I would be tempted to buy it to match it with a pair of Klipsch La Scala that I currently keep disconnected. Do you seriously think it's a good choice? A couple sent to Italy would cost me 516 euros, but my doubt is about assistance if it should have problems or it breaks down where I go? It would be interesting, in addition to knowing how it sounds, to have the schemathics. Let me know
Giuseppe

I only have experience with the original so not in a position to say how these clones would be.

 

[audiophile.1963]

Probably the amp that I saw is different:

Finished Pass A30 Mos Single-ended Pure Class A Power Amplifier Mono 30w Hifi Audio Amp - Buy 30w Audio Power Amplifier,Power Amplifier,Amplifier Product on Alibaba.com

Finished Pass A30 Mos Single-ended Pure Class A Power Amplifier Mono 30w Hifi Audio Amp - Buy 30w Audio Power Amplifier,Power Amplifier,Amplifier Product on Alibaba.com

www.alibaba.com

...or the cabinet is different
Giuseppe

 

[fpitas]

Sonic quality aside, you'd be smart to have someone knowledgable check out the internal wiring, especially at the power inlet. Over on the Pass Labs forum they've pulled apart plenty of clones that were downright dangerous. These people aren't afraid to pirate designs, so there's no reason to trust their integrity.

 

[restorer-john]

Sonic quality aside, you'd be smart to have someone knowledgable check out the internal wiring, especially at the power inlet. Over on the Pass Labs forum they've pulled apart plenty of clones that were downright dangerous. These people aren't afraid to pirate designs, so there's no reason to trust their integrity.

I agree. There's no way I'd be plugging in some random imported clone without checking the electrical safety of it.

 

[ModDIY]

The amp is mounted with PCBs implemented and built by the Zero Zone brand.

Usually their circuits look quite honest and well done. I also recognize the power supply capacitors used on many of their amps.

2 years ago I mounted an amplifier with TI LM1875 chipamps, mono circuit with double LM1875, I had 2 transformers for a double mono.
In short, the sound was good, no whistling and very quiet. On the other hand Zero Zone had sanded the number of the chipampas, why?? a copy maybe.

About the Pass clone, in the photo, it seems to me that the ground is not connected to the AC socket, to check. Also measured the DC voltage at the HP output.

 

[audiophile.1963]

Sonic quality aside, you'd be smart to have someone knowledgable check out the internal wiring, especially at the power inlet. Over on the Pass Labs forum they've pulled apart plenty of clones that were downright dangerous. These people aren't afraid to pirate designs, so there's no reason to trust their integrity.

This is my fear and unfortunately I am not competent in electronics, I only have a trained ear to listening. The price of these devices makes them attractive; It should be perfect to have the schemathics.
Giuseppe

 

[fpitas]

This is my fear and unfortunately I am not competent in electronics, I only have a trained ear to listening. The price of these devices makes them attractive; It should be perfect to have the schemathics.
Giuseppe

Luckily, you won't need the schematic for safety checking.

 

[Tom C]

From the looks of the photo, the case alone is worth the price.

 

[fpitas]

From the looks of the photo, the case alone is worth the price.

Granted. And ModDIY recognizes the bare PCBs used as made by Zero Zone. Might be nothing at all wrong, but I'd still check the safety aspects.

 

[audiophile.1963]

Granted. And ModDIY recognizes the PCBs used. Might be nothing at all wrong, but I'd still check the safety aspects.

I'm not able
Giuseppe

 

[ModDIY]

Granted. And ModDIY recognizes the PCBs used. Might be nothing at all wrong, but I'd still check the safety aspects.

Attention I do not believe that it is Zero Zone who assembled the Pass clone. They only do the implementation and assembly of the circuit with parts, but other companies assemble the amplifier, so don't take any risks, and assume that the ground is not correct.

The ideal would be to show us internal photos close to the input AC cable.

 

[audiophile.1963]

I wrote in China asking pictures of the amp inside and they answered me that I will have these pictures on monday
Giuseppe

 

[HarmonicTHD]

Wow. Alone the cases are worth it. And if you don’t like the amp modules, just throw them out and reuse the PSU and the case. It even seems to have a soft start or so. Very tempting.